D-Link DWS-4026 User Manual page 427

Software User Manual
12/10/09
Field
MAC Authentication
Redirect
Redirect URL
Wireless ARP
Suppression Mode
L2 Distributed
Tunneling Mode
Document 34CSFP6XXUWS-SWUM100-D7
Table 263: Wireless Network Configuration (Cont.)
Description
If you enable MAC authentication, wireless clients must be authenticated by the AP in order
to connect to the network. To use MAC authentication, configure the client MAC addresses in
one of the following databases:
• Local
• RADIUS
In the database, you set a default action to either accept or deny that client or use the global
action configured on the WLAN > Administration > Advanced Configuration > Global
page.
MAC authentication is useful in networks that operate in Open mode to grant or deny access
to clients with specific MAC addresses. MAC Authentication can also be used in conjunction
with 802.1X security methods, in which case the MAC Authentication is done prior to the
802.1X authentication.
Select the HTTP option in the Redirect field to redirect wireless clients to a custom Web page.
When redirect mode is enabled, the user will be redirected to the URL you specify after the
wireless client associates with an AP and the user opens a Web browser on the client to
access the Internet.
The custom Web page must be located on an external Web server and might contain
information such as the company logo and network usage policy.
Note: The wireless client is redirected to the external Web server only once while it
associated with the AP.
Redirect functionality allows you to implement captive portal functionality; a captive portal is
often used at Wi-Fi hotspots to provide branding for the hotspot provider and/or display a legal
disclaimer, which the user can click-through to access the Internet.
Enter the URL where all initial HTTP accesses should be redirected to. This field is accessible
only when HTTP is selected as the redirect type.
Enable the mode to allow the APs to reduce the number of broadcasted ARP requests on the
wireless interfaces. Reducing broadcasts helps conserve power on the wireless clients. The
wireless clients that use power-save mode must wake up and use more power when they
detect broadcast frames.
Note: Enabling this feature slightly degrades AP packet forwarding performance due to
extra packet filtering to find DHCP packets and extra processing for ARP request and reply
packets. Networks that do not use IPv4 should not enable this feature.
The distributed L2 tunneling mode supports L3 roaming for wireless clients without forwarding
any data traffic to the Unified Switch. Use the menu to enable or disable the mode.
L2 tunneling is recommended when the Unified Switch does not support hardware forwarding
acceleration or hardware-based L2 tunnels.
Note:
1 When there is only one switch managing all APs and that switch goes down, all APs shut
down their radios and the tunnel is terminated. After the switch recovers and the AP
becomes managed again, the client that was previously tunneling traffic will re-associate
and obtain an IP address on the network where its currently located. This IP address will
be different from the IP address it was using when it was tunneling, and the traffic will not
be tunneled.
2 If the network has peer switches and the tunnel is established between the APs managed
by the peer switches then, when a switch managing the home AP fails, the switch managing
the association AP detects the failure and terminates the tunnel. At this point the client is
disassociated. When the client re-associates it obtains a new IP address.
3 If the switch managing the association AP fails, then the scenario is the same as in item 1
above. The AP takes down all radios and the clients disassociate.
D-Link Unified Access System
Basic Setup Page 427